This invention relates to an improved dry transfer decal.
Dry transfer decals have been known for some time. Their development was as a replacement for the prior art water slide decals and constituted an effort to provide a more convenient system for applying decals. Typical of dry transfer decals are those described in MacKenzie, U.S. Pat. No. 3,131,106, Karlan U.S. Pat. No. 3,013,917 and Tordjman U.S. Pat. No. 3,741,787.
The dry transfer decals described in the above references utilize a low tack adhesive that is basically dry to the touch. These adhesives are generally weak and consist of soft wax-like materials that will bond by the application of pressure to paper or similar materials. Once applied to a surface, such decals are easily damages by abrasion though they do adequately satisfy the artistic or design purpose for which they are fashioned.
There remains, therefore, many instances when a more rugged abrasion resistant dry transfer decal is required. For example, industrial labels, sign labels and hobby model labels generally require more abrasion resistance than that available from products disclosed in the above identified references.
Water slide labels have also been commonly used to decorate plastic models made by hobby makers. Such decals are quite fragile and do not adhere well. If the decal is soaked in water for too long a period of time, the gum adhesive is washed from the decal and it will not adhere to a surface. Placement of such a decal is also a problem since such decals must slide about until the correct position is achieved. This spreads the adhesive into areas of a surface where the adhesive is not desired.
To overcome such described difficulties, ordinary high tack pressure sensitive dry decals have been suggested, and in an industrial environment such decals are described in Asnes U.S. Pat. No. 2,733,997. However, the decal disclosed in the Asnes patent is quite difficult to position accurately due to the fact that it is printed on opaque substrates such as wax or polypropylene coated kraft paper. Also due to the high tack nature of the adhesive, once the decal touches the surface it tends to bond tightly, precluding further movement. Consequently it is almost impossible to utilize such a decal for a plastic model hobby kit, for example. To overcome such problems, the present invention was devised.